Are you worried about your sleeping habits? We asked sleep expert Heather Darwall-Smith to explain the science behind getting a good night’s sleep.
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At a time when we’ve never been more aware of how important sleep is, more and more of us are struggling to get a good night’s shut-eye. Nearly half of the UK has trouble falling asleep once a month and one in five adults finds it difficult to fall asleep every single night.
“People are starting to think so much about sleep and obsess about it using tools like Fitbits, when actually the harder we try to sleep the worse it gets,” says Heather Darwall-Smith, a sleep expert at The London Sleep Centre. Heather began working in sleep after running stress awareness courses and noticing the question, “Why can’t I sleep?”, kept being asked over and over again.
“We don’t know what comes first, poor sleep or mental health,” says Heather. “But ultimately sleep is a biological fact. It will happen naturally on its own. So, I wanted to get the bottom of why we’re having such a problem with it.”
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There are three key rules to sleep: creating a cool, calm, comfortable and quiet sleep environment, having a relaxed mind and, lastly, a relaxed body. “Your sleep environment is the easiest bit to fix because you can buy things to improve your bedroom,” says Heather. “The other two are much harder to solve.”
In her book, The Science Of Sleep: Stop Chasing A Good Night’s Sleep And Let It Find You, Heather explains that while sleep is extremely personal and individual, it’s also a science and there are reliable methods, which cut through all the myths and fads, that can help us start to get a good night’s sleep.
Here, Heather explains the science behind sleep and lays out eight simple ways to help transform your sleeping habits one night at a time.
How does sleep actually work?
“Sleep is a tale of two halves,” says Heather. “In the first half of the night we get lots of deep sleep and in the second half of the night we get less deep sleep and more rapid eye movement (REM) sleep. The two work together in a very synergistic way.”
There are three stages to sleep. We move through them in a number of cycles each night, drifting in and out of sleep and wake in the process.
When our head hits the pillow we go into stage one sleep for 10 minutes. Here the brain slows down, but we’re still in a state of wakefulness and vaguely alert.
We spend most of the night in stage two sleep. This is light sleep. We’re unconscious, our heart rate slows down and our core body temperature decreases, but it can feel really similar to wakefulness especially if you’re a light sleeper. This lasts for around 20 minutes.
This is really deep sleep. It usually happens in the first half of the night. This is the stage where the body restores itself and rejuvenates. Our blood pressure drops even further, our breathing slows right down and becomes very rhythmic. The hormones that manage appetite control are released here.
The sleep cycle
After moving through the three stages of sleep, we cycle back up through the stages again: from three, into two, through one and then into REM sleep. During REM, our brain is active and we have dreams. The entire cycle takes around 90 minutes. We go through four to six of these cycles during the night and as we do it’s very normal to move around and wake.
Relaxed mind and relaxed body
The more stress hormones – adrenaline and cortisol – we have going through our body, the harder it is for us to sleep. “If you imagine shaking a bottle of fizzy drink, the pressure and bubbles created are like our stress hormones and adrenaline,” says Heather. “All those hormones build up during the day. When you go to bed and pause, that bottle opens and it’s carnage.”
Bringing down our stress levels is important to relax the brain and body as much as possible. “We need to find a way to open that bottle slowly and steadily through the day,” says Heather.
What winds people down is very individual. For some it might be meditation and a warm bath, others might prefer a gentle walk or yoga stretches. Despite this, Heather still recommends some fail-safe methods, backed by science, that will help everyone get a good night’s sleep.
Heather’s 8 scientifically-approved ways to get a good night’s sleep
Stop staring at screens
“One overall thing I ask people to do is to step away from screens,” says Heather. Science is clear that blue light suppresses melatonin – the ‘sleepiness’ hormone – but that’s not the only reason to put your phone away in the evenings.
“Phones are designed to keep us hooked, which keeps us awake and stimulated,” says Heather. She advises turning notifications off on your phone in the evenings. This means you can still listen to a podcast or music without getting distracted.
“Use your phone as a tool, rather than a device that’s going to keep you occupied,” she explains.
Set a wake-up time and stick to it
“From a scientific perspective, the best thing you can do to get a good night’s sleep is get up at the same time every morning,” says Heather. “This sets your circadian rhythm, or body clock, for the day.”
Getting up at the same time every day triggers your body clock to begin the process of producing melatonin 12 to 14 hours later, which will make us ready for bed.
Swap coffee for light
If you struggle to get up at the same time every morning, Heather recommends using light to your advantage. “There’s a part of the brain called the suprachiasmatic nucleus. This receives light and sets everything up for the day,” says Heather. “Getting outside or looking at natural light out of a window is highly beneficial to set that clock.” During the winter months you can try putting daylight bulbs into your overhead lights instead.
Heather explains that creating a routine in the morning of getting 10 minutes of natural light followed by 10 minutes of movement (“even if that’s just putting on loud music and dancing around your bedroom when you’re getting dressed”) is more powerful than relying on stimulants like coffee to set your brain up for the day. “This sequence is very powerful because you are setting up your internal rhythm,” notes Heather.
Make time to wind down in the evening
Sleep pressure is a biological response that makes us want to go to sleep. If we don’t build up enough sleep pressure through the day we won’t be able to settle easily or sleep for long.
“Sleep pressure is created from the moment we get up when the brain begins building up a powerful molecule called adenosine. It’s a very natural process,” Heather explains. “Adenosine and melatonin create a sleep gate that you build up to help you fall asleep at night time.”
Things that get in the way of building up sleep pressure are caffeine (which “sticks to receptors in the brain that block adenosine”), blue light and exercise. “If you do a HIIT class at 8pm at a gym full of bright lights, you’ll get a massive flash of adrenaline, your body will heat up and it will disrupt your sleep pressure,” says Heather.
To get a good night’s sleep you must allow yourself time to cool down. This could be through taking a cool shower, sitting in low light at home, or going to bed a bit later if you have done exercise in the evening. “You’ve got to work with your biological rhythms,” says Heather.
Limit your time in bed
If you have sleeping problems limiting the time you spend in bed can be hugely beneficial. “Someone might say, ‘I’m going to bed at 9.30pm so I can get more sleep, but if you have trouble nodding off this won’t work,” says Heather.
“You need to train the body to know when it’s time to sleep,” Heather explains. “If you spend too much time in bed it fragments your sleep because your brain doesn’t think you need one solid block of it anymore,”
Help your body recognise that your bed is just for sleep and that everything else happens outside the bedroom.
Make time to worry
“Fitting in time to worry might seem counterintuitive,” says Heather, “but it can be really beneficial.”
In the last couple of hours before you go to bed spend 15 minutes writing down all your worries and concerns into a specific notebook. Then slam the book shut and go to bed.
“Making time to worry is highly effective,” says Heather. “There’s something very powerful in physically writing things down, it gives the worries running around in your head somewhere to go, so you can come back to them and deal with them in the morning.”
Get in tune with your senses
Sleep is a very sensory experience. Tuning into our senses if we’re struggling to fall asleep is a good way to help anxiety. Heather recommends a sensory integration exercise called the ‘5, 4, 3, 2, 1’ method. It allows you to shift your attention from the feelings in your mind and body to what’s going on around you through the five senses instead.
As you lay quietly in bed take a moment to breathe deeply and explore your environment in this way:
- Think of five things you can see: your hands, the ceiling or the sky, a picture on the wall.
- Think of four things you can physically feel: your feet on the ground, a ball, your back on the mattress.
- Think of three things you can hear: the sound of the wind, the hum of the central heating, your partner breathing.
- Think of two things you can smell: clean clothes, soap.
- Think of one thing you can taste: toothpaste, coffee, or fresh air.
“This helps to calm you down when your mind is bouncing around with anxious thoughts,” says Heather.
Look at the sky
“I really invite people to go out and look at the sky if they just can’t sleep,” says Heather. Watching how the sky moves and changes will give you a moment to pause and help you focus on something other than anxious thoughts.
“Whatever is happening, even if your sleep is bad at that moment, it’s not always going to be. Biologically, the absolute fact of the matter is, you can sleep.”
Know what’s normal during sleep
Waking in the night
Sleep is a very individual thing and most disruptions we have in the night are very common. There are multiple reasons why we might be a light sleeper and our sleep changes over our lifetime.
“When we’re young our bodies and brains are growing really fast so we need deep sleep,” says Heather. “As we get older, we’re not growing anymore so, while we still do need enough sleep, the quality changes.”
As our sleep cycle repeats into the second half of the night, we also begin to get more REM and less deep sleep. This switch often happens around 2am or 3am. “This is why waking up at this time of night is really, really common,” says Heather.
Don’t stress out about getting eight hours of sleep
Getting a solid eight hours of sleep is unrealistic. “The American Sleep Academy of Medicine recommends adults have between seven and nine hours of sleep a night, but that doesn’t mean you’ll sleep in one solid block for that long,” says Heather. “Thinking this just causes anxiety and leads to less sleep.”
Everyone’s sleep is different
Sleep is completely individual. “I might need a completely different amount of sleep to someone else,” explains Heather. Our genetic underpinning means some people are night owls and others are morning larks.
“If you are struggling to sleep and not feeling rested, rule out whether you have a sleep disorder, like sleep apnoea (a breathing disorder) or periodic limb movement disorder. If you still can’t sleep, something psychological is happening.”
Images: Getty, Heather Darwell-Smith
Heather Darwall-Smith, sleep expert, psychotherapist and author
Heather is a sleep therapist at The London Sleep Centre. She is a qualified psychotherapist with an MA in mindfulness-based core process psychotherapy from The Karuna Institute. She is currently working towards a PGDip in sleep science at the University of Oxford. Heather’s book, The Science Of Sleep, is out now, published by DK.